Liquid pressure remote-control system



July 18, 1944.

F. s. EvEs ETAL 2,353,884

LIQUID PRESSURE REMOTE CONTROL SYSTEM original Filed Aprila'. 1941 `2 Sheets-Sheet l 2, 91 92 39 40 Fla] F/GQ i fm 66. 53 26 53: 8 3f 52 5r #54 62 \27 28 '37 /.29 /JO 38 y a 48 4s 46 j A 3 v46 413// 75,1 33 \44 39 Si *"0 41 l \42 Z #veA/'ro S 3"1 FREDERICK .5. Evi-:,R

July 18, 1944- F. s. Evl-:s ET AL 2,353,884

LIQUID PRESSURE REMOTE CONTROL SYSTEM Original FilledApril 21, 1941 ZSheetS-Sheei; 2

[AMEN-raras FRED L EmcKS. Eve-s, I, b Flur C. BnMFvKo/Ju-.zudl

y 6in1-nubi H.D. Bnl-'Fans Duwyc. aan" A 'awt TNA 'rens Patented July 18, 1944 UNITED STATES PATENT OFFICE LIQUID PRESSURE REMOTE-CONTROL SYSTEM company, jointly Original application April 21, 1941, Serial No.

389,674, now Patent No. 2,335,269, dated November 30, 1943. Divided and this application September 18, 1942, Serial No. 458,884. In Great Britain April 29. 1940 8 Claims. (Cl. 6,0--54.6)

This invention relates to liquid pressure remote control systems, and it has for its primary object to provide an improved form and construction of system in which means are incorporated to ensure that the slave unit or units of the System are operated in accordance with movements imparted to the transmitter pump or like master unit of the system.

This application is a division of application Serial No. 389,674, filed April 21, 1941, now Patent No. 2,335,269.

The invention has particular utility in connection with the order telegraph devices Such as are used on ships for the purpose of transmitting instructions, say from the bridge to the engine room. It is, therefore, a further object of the invention toprovide a robust and efficient order telegraph system which is operated hydraulically.

A further object of the invention is to provide means for ensuring that the operated member, for examplethe distant pointer of a ships telegraph, is moved accurately to any one of a plurality of predetermined positions, irrespective of any slight inaccuracies which there may be in the transmitting mechanism, due for instance to the use of long lengths of pipeline or to rough usage of the system.

In a liquid pressure remote control system having a transmitter pump arranged to bring about reciprocation of one or more motor units, according to one feature of the invention, locking means are provided in the transmitter pump and come into action automatically at a predetermined stage to prevent further operation of said transmitter pump until Such time as said locking meansl are released by the motor unit or units.

Further, a liquid pressurel remote control System is provided in which a transmitter unit comprises a pai-r of cylinder and piston devices operated by a spindle, wherein means responsive to the direction in which the spindle is rotated are arranged to connect operatively one or other of the cylinder and piston devices to the spindle, depending upon the direction in which the saidA Spindle is rotated, the unconnected device remaining inoperative all the time that said rotation is continued. l

The invention further provides for a liquid pressure remote control system, a transmitter pump comprising a pair of cylinders, pistons Slidable in said cylinders, a rotary actuating spindle, and selective drive transmitting means whereby one only `of the pistons is moved relative to its cylinder-when the spindle isV rotated clockwise, and the other of said pistons is alone moved relative to its 'cylinder when the spindle is rotated anti-clockwise.

The invention is illustrated by way of example inthe Aaccompanying diagrammatic drawings, in which- Figure 1 Shows a Simple form of remote indicating system;

Figure 2 Ais a sectional elevation drawn to an enlarged scale to show the internal construction of the transmitter pump, the section being taken on the line 2--2 of Figure 3;

Figure 3 is a sectional elevation of the transmitter pump taken on the 4line 3-3 of Figure 2;

Figure 4 is a fragmentary view corresponding to Figure 3 but'showing the internal parts in different positions; and e Figure 5 is a sectional 4elevation of one of the transmitter ratchet devices, the Section being taken on the line 5-5 of Figure 2.

The I liquid pressure remote control system which is shown in Figure 1 comprises a transmitter unit A which is provided with an operating handle 2|) and wheel 2| and is connected bya pair of pipe lines 22 and 23 With a pair of motor units B- and B', said motor units being arranged in parallel across the pipe lines 22 and 23. Each is provided with a spindle 24, which is arranged to move angularly in steps, one step for each complete rotation of the wheel 2| of the transmitter unit A, the construction of the motor units being described more fully in our ccpending application Serial No. 389,674, iiled April 21, 1941.

The transmitter unit A comprises a substantially rectangular casing 25 having end plates 26 and 21 carrying bearings 28 and 29 for an operating shaft or spindle 30, to which latter the wheel 2| (Figure l) is secured. Within the casing 25 the-shaft 3|! carries a pair of ratchet devices indicated generally at 3| and 32, each of said devices comprising a substantially cylindrical drum member 33 which ris freely rotatable upon the shaft 3U, and which carries a pawl 34 (see Figure 5). Thispawl is accommodatedwithin a cut-away portion of the drum member 33 and is pivota-lly mounted upon a pin'35, a leaf spring to transmit a drive in opposite directions, so that when the shaft 30 is turned in a clockwise direc- Y tion (as viewed from the righthand end of said shaft) the drum member 33 of the ratchet device 3| is rota-ted, but the drum member of the ratchet device 32 remains stationary.y Conversely, when 61 into engagement with the conical recesses 62. Axial projections 68 formed upon the thrust pieces 64 and 65 are adapted to butt against one another, thus limiting the extent to which the thrust pieces 64 and 65 can approach one another. The distance separating the spigots 68 ,when the parts. are disposed in the positions shown Y in Figure 2, with both of the locking levers 55 the shaft is rotated in an anti-clockwise direction, the ratchet device 32 is driven, while the.

ratchet device 3| slips. Y

The bottom of the casing 25 is formed-with a pair of cylinders 39 and 40, which are provided with screw plugs 4| and -42 for connection tothe pipe lines 22 and 23 respectively (see Figure 1). Pistons 43 and 44 are slidable within the cylinders 39 and 40, each of said pistons being-- connected pivotally with a corresponding link 45 by means of a pin 46. 'I'he upper vend of the link -45 and 56 in their lowered and operative positions, is arranged tobe sufficient for allowing only one of the balls 66 or 61 to be ejected from its recess 62. Thus either of the locking levers 55 and 56 can be raised, but when one is raised the other is positively locked in its down position, the parts 64, 65, 66, 61 and 68 constituting an axially continuous thrust member which prevents the other f ball ,66 or 61 from moving out of its recess 62.

The shaft 30 is shown in its zero position in y Figures 2k and` 3, and it will be seen that it can is pivotally connected at 41 with a follower lever i 48, which latter conveniently comprises a pair of bars arranged side by side, as seen in Figure 2. The follower lever 48 is pivotally anchored to the casing 25 by means of a pin 49 and at a position approximately half-way along its length it carries a freely rotatable follower roller 50 mounted This roller is adapted to engagey upon a pin with an eccentric cam 52, which is .securedto or forms part of the correspondingydrum-member 33, so that as the latter rotates, downward force is imparted to thefollower lever 48 during every1 As each complete revolution. of the shaft 30 corresponds with one step of movement of the motor units B and B', locking means are provided for preventing the direction of rotation of the shaft 30 from being reversedy except when said shaft is in a predetermined zero position, for example with the handle uppermost. For this purpose each of-theldrum members 33 -is formed at one place in its periphery with a substantially trapezoidal recess 53, which is adapted to be engaged by a correspondingly shaped projection 54 formed upon the underneath of a locking lever. The locking lever for. the ratchet device 3| is indicated at 55, while theflocking lever for the ratchet device 32 is shown at 56, each being pivoted to the casing at 51.V The slop ing surfaces of the recess 53 and'projection 54.

are arranged so that theprojection rides out of the recess as the corresponding drum member 33 rotates, although, of course, when the locking lever 55 or-56 is `held down, the rotation of the drum member 33 is positively prevented. The locking levers 55 and 56 pass through substantially rectangular notches 58 and 59 in a thickened web member v6|.'I formed in the top of the casing 25, saidweb member having a longitudinal bore 6| intersecting both of the notches 58 and.

and 65, which in turn urge a pairof balls 66 and 75 1 the force exerted by springs as will be herein- 55? step 10 which is adapted to be engaged by a profthe eccentric cam 52.

be rotated in either direction, the parts resuming their original positions when one complete revolution has taken place. supposing, however, that the shaft has been rotated through part of a revolution with, say, the ratchet device 3| driving, and an attempt is made to reverse the direction of rotation, the drive will be transferred from the ratchet device 3| to the ratchet device 32, the drum member 33 of which latter is, of course, prevented from rotating, as its locking lever 56 is being positively held down by the ball 61. Therefore reverse rotation cannot take place and it is necessary for the movement of the shaft 30 to proceed in uni-directional units, each composed of one complete revolution. The locking levers and 56 are each urged towards their operative positions by a coiled compression spring 69.

Auxiliary locking means are provided for arresting-the movement of the shaft 39 whenever it reaches its zero position should the piston 43 (orv 44) which is being operated not have reached its fullyA raised position. It should be mentioned that the pistons 43 and 44, in being moved downwardly by the corresponding eccentric cam 52, force liquid into the motor units B and B' against after explained, so that when the piston 43 (or 44) is free to rise, liquid is expelled from the motor units B and B at a moderate pressure and thus raises said piston as far as is permitted by Separate locking means are provided for the respective ratchet devices 3| and 32, said means being similar in construction and being shown in Figures 3 and 4. The end of the locking lever 55 (or 56) is formed with a jection 1| formed at the top of a catch lever 12, which is pivoted to the casing 25 at 13, and is urged resiliently towards the locking lever by a coiled compression spring 14. At its lower end, the catch lever 12 is formed with a pin 15, which is adapted to co-operate with a roller 16 pivotally mounted upon a pin |1 at the free end of the follower lever 48. A restoring arm 18, piv- .r oted to the casing 25 at 19, has at its ,lower part arm 18 is urged towards the roller 16 by a coiledv compressionspring 82 and when the piston 43 is ator adjacent its uppermost position, the roller 16rengages with the cam surface 80, which is,v obliquely disposed so that the force of the spring 82 is lutilised to raise the piston 43 (or 44) through the last portion of its upward travel, and

to retain it and the follower lever 48 in their fullyv raised positions, kso long as'thej corresponding drum member 33 is in its zeroposition', as shown in Figure 3. It will be noted that withthe' parts iin this position the'roller'l engages the pin '15, and thus deects the catch lever 12, so that the catch projection 'Il is heldi out of. engagement with the step 1D of the locking lever.

The camsurface S'isarrariged'so as to lie substantially parallel with the direction in which the roller 16 moves as the piston-431er 44) proceeds downwards within'its cylinder, so that the spring 82 then exerts no force atr all tending 4to move the follower lever about its pivot 49. This is clear from Figure 4, which indicates the position of the parts when the drum member 33 of the ratchet device ,3l has been turned in the direction of the arrow, the recess 53 having reached the position shown. It will be seen that the roller 'It has left the pin 'l5 of the catch lever 12, so that the upper end of the latter bears against the locking lever 55, said locking lever, of course, being in its raised position. As the drum member 33 continues to turn, the piston 43 is moved to the bottom of its stroke and then as the drum member 33 proceeds with the second half of its revolution, the piston 43 is forced upwardly by the liquid which is returned at moderate pressure from the motor units B and B. This action is not, of course, assisted by either the eccentric cam 52 or the cam surface 8l of the restoring arm i8; if, therefore, the piston 43 lags in relation to the eccentric cam 52, the catch lever T2 remains operative when the recess 53 is next engaged by the projection 54 of the locking lever, and the catch projection .'l consequently engages with the step IQ, said projection thus positively holding the drum member 33 against further rotation in either direction until such time as the piston d3 has reached its fully raised position. When this happens the roller 'l5 re-engages with the pin 'l5 and releases the catch projection 'ii from the step lll.

The interior of the casing 25 is used as a storage reservoir for spare working liquid and it is connected by a passage 83 with a small orice 84 leading into the cylinder 39 (or 49) at a position which is below the lower edge of the piston 43 or 4Q) when the latter is fully raised. The cam surface 8l) is arranged to take charge of the piston just before the orifice 8e is uncovered so that the piston and follower lever 48 are raised, and remain in their raised positions, despite the fact that the interior of the cylinder 39 (or Ml) is connected with the reservoir so as to allow the pipe line 22 (or 23) to breathe in the known manner.

When the piston 43 (or 4t) moves downwardly, the orice 84 is closed at the very rst part of the stroke and thereafter liquid pressure is created in the cylinder.

The transmitter described is, of course, given n merely as an example and various modiiications in the construction may be made without departing from the invention.

What we claim is:

l. In a liquid pressure remote control system, a

@l 2'. In a liquid pressure remotecontrol system,4 a transmitter 'pumpcomprising a pair :of piston and 'cylinder.=units,z 'a ldriving' spindle; a pair of ratchet'an'dpawl'devices mounted on said spindle so that 'one ltransmits a rotary drive in only one direction andthe other only inithe other direction, and-'a pair lof cam and follower devices driven' respectively by the ratchet devices each to reciprocate the correspondin'gpiston relativev to its cylinder, the "drivinglspindle being capable of making ai plurality-of l'complete revolutions Tin sequencein they samedirection for repeatedly vre' ciprocating that piston which corresponds. to the direction of rotation of the spindle.

3. In a liquid pressure remote control system, a transmitter pump comprising a pair of piston and cylinder units, a driving spindle, a pair of ratchet and pawl devices mounted on said spindle so that one transmits a `rotary drive in only one direction and the other only in the other direction, a pair of cam and follower devices driven respectively by the ratchet devices each to advance the corresponding piston within its cylinder, and means for returning each piston as the cam presents a surface of decreasing radius to the follower, the driving spindle being capable of making a plurality of complete revolutions in sequence in the same direction for repeatedly reciprocating that piston which corresponds to the direction of rotation of the spindle.

4. In a liquid pressure remote control system. a transmitter pump comprising a pair of piston and cylinder units, a driving spindle, a pair of ratchet and pawl devices, each comprising a driving member and a driven member, mounted on and actuated `by said spindle so that one transmits a rotary drive in only one direction and the other only in the other direction, reciprocating means connecting the ratchet devices With the respective pistons, and means for locking the driven member of one of the ratchet and pawl devices when the spindle is turned in a direction appropriate to actuate the other ratchet and pawl device, whereby the spindle is prevented from being reversed in rotation until such time as said locking means is released.

5. A liquid pressure remote control system as claimed in claim 4, wherein the locking means are actuated by rotation of one ratchet and pawl device and serve to prevent rotation of the other ratchet and pawl device.

6.v In a liquid pressure remote control system, a transmitter pump comprising a pair of piston and cylinder units, a driving spindle, a pair of ratchet and pawl devices, each comprising a driving member and a driven member, mounted on and actuated by said spindle so that one transmits a rotary drive in only one direction, and the other only in the other direction, reciprocating means connecting the ratchet devices with the respective pistons, means for locking the driven member of one of the ratchet and pawl devices when the spindle is turned in a direction appropriate to actuate the other ratchet and pawl device, whereby the spindle is prevented from being reversed in rotation until such time as said locking means is released, auxiliary lockauxiliary locking means as the piston assumes its' fully returned position. y

7. In a liquid pressure remote control system,

a transmitter pump comprising a pair of pistony and cylinderfunitsr a rotatal'ile driving spindle for operating said unitsone fullccycle of reciprocation perfrevolution, means responsive -to the direction 'of rotation of Vsaid spindle f or selectively actuating-V one or .the other of said units, a ratchet mechanism :connected 4with thespindle, locking means associated Withvsaid ratchet mechanismto prevent rotation of the spindle in one direction, and means responsiveto rotation of the spindle in the :opposite direction for bringing said Vlocking means intoy action vand thereby preventing zthe rotation of said spindle from-being reversed.` L f 1 8: A vliquid -pressure remote control system as claimed in claim 7, includingvmeans for releasing `thelocking means each time the spindle reaches a predetermined zero position, thereby allowing the direction of rotation to be reversed only at that position.

FREDERICK SYDNEY EVES. G. M. D. BAMFORD, D. C. BAMFORD, Administrators of the Estate of Alfred Chadbum Bamford, Deceased. 

